The terminology, wallboard, refers to one or more panels or panel sections having major surface areas, which form gypsum wallboard or, alternatively, portland cement wallboard or alternatively, in situ polymeric foam panels of US 2007/0099524 A1. U.S. Pat. No. 5,017,312 discloses chopped glass fiber mats tested for flexure and tensile properties according to ASTM D 790-84a “Standard Test Methods for Flexural Properties of Unreinforced and Reinforced Plastics and Electrical Insulating Materials,” and ASTM D 638-84 “Standard Test Method for Tensile Properties of Plastics.” The tests are performed on mats having random oriented chopped fibers and mats having directionally oriented chopped fibers.
U.S. Pat. No. 7,141,284 B2 discloses a reinforcing web having a rewettable coating to solubilize in a slurry of a joint compound and form an adhesive bond with the joint compound.
Open wallboard seams are formed between abutting sections of gypsum wallboard that meet side-by-side, or that meet at inside corners. To fill and cover an open wallboard seam, a wallboard joint is constructed, by applying a joint compound reinforced with an imbedded reinforcing tape. Additional seams can appear as cracks in the wallboard, which are repaired by constructing wallboard joints.
The joint compound is in the form of a shapeable slurry that fills the seam. The reinforcing tape is applied to extend across the filled seam, and to overlap the edge margins of the wallboard abutting the filled seam. It is desirable that the reinforcing tape is foldable to form a lengthwise crease. The crease is needed for conformance at an inside corner of a wall meeting another wall or a wall meeting a ceiling, wherein wallboard sections of the walls and ceiling meet one another at an angle less than 180 degrees. A wallboard joint is constructed at the inside corner by applying joint compound to imbed the creased reinforcing tape.
A joint tape made of paper is capable of forming a crease for installation at inside corners wherein wallboard sections meet one another at an angle of less than 180 degrees. Moreover, commercial tooling has been developed to use paper tape for machine construction of a wallboard joint. The tooling continuously dispenses the paper tape and continuously dispenses a joint compound slurry to imbed the tape. Further, the tooling shapes and smoothes the joint compound slurry. A drawback of paper tape is that the paper is weakened by becoming saturated with water from the slurry, and is incapable of passing air bubbles that are trapped behind the paper tape during construction of a wallboard joint.
Instead of a paper tape, a fabric tape has been used to reinforce a joint compound. A thin porous fabric has been manufactured with random laid glass fibers adhered to one another with a urea-formaldehyde binder. The tips of the glass fibers tend to poke out, which is irritating to the touch when handled by a worker. Moreover, a binder coated fabric resists being folded, and is not able to form a crease for conformance to an inside corner. Further, the binder covered fabric is not adaptable as is paper for handling by machine tooling for fabricating a wallboard joint. Such drawbacks deter using a binder coated fabric for reinforcing a joint compound.